The present invention relates to the transfer of fluid. More particularly, the present invention relates to fluid transfer systems which utilize a low-friction flexible wall within a hollow body to facilitate fluid transfer.
There are a great number and a variety of pumps in the art. The typical purpose of the pump is to move air or liquid from one location or container to another. Generally, a piston is movable within the pump to create a negative pressure or vacuum which moves the fluid from one location to the other. Pumps can be manually actuated or connected to an electronic or mechanical device. One of the problems associated with prior art pumps is that they have typically produced a tremendous amount of friction. This limits the efficiency of the pump and increases the cost of pumping the air or liquid from one location to another. Another problem associated with prior art pumps is that they can only pump liquid to a certain height. The higher the height of liquid, the harder it is to pump due to gravitational forces exerted upon liquid.
It has been found that using an elastomeric wall decreases the energy needed to create fluid flow. Such fluid flow can be utilized for many applications. For example, such low-friction flexible walls can also be advantageously used in applications where fluid is removed from a holding tank. In such holding tanks, and particularly hand-held portable holding tanks, the influx of air during fluid removal creates pockets of air within the fluid that causes the draining fluid to surge periodically and unexpectedly, potentially causing spills of the fluid. Such spills can potentially be a hazard to the operator of the tank, or the environment, such as in the case when oil or gasoline is drained from containers. With an elastomeric wall installed in a base of the tank or container, and allowed to travel the length of the container, the fluid flows smoothly and accurately. Fluid transfer systems having such an elastomeric wall also enable the fluid pumped into the system to be pumped to great heights as the system overcomes gravitational forces.
In other applications, vehicles, such as aircraft or spaceships, require a tremendous storage space for the fuel required for their travel. The storage of such fuel within the aircraft results in a heavier aircraft which requires additional fuel to be burned during its travel. It would be advantageous to provide a system for transferring fuel to the aircraft or spaceship, which does not require the aircraft or spaceship to store such a heavy load.
The present invention resides in a closed fluid transfer system intended to facilitate fluid flow. The system generally comprises a fluid source and a hollow body in fluid communication with the fluid source through an inlet of the hollow body. The hollow body includes a flexible and expandable wall at one end thereof, and an outlet distal from the flexible and expandable wall. Means are provided for transporting fluid from the fluid source to the hollow body. Such means typically includes a pump associated with the system.
In a first embodiment of the invention, the hollow body comprises a fluid conditioning chamber. A tube extends from the fluid source to the hollow body inlet. The tube typically comprises a siphon tube. Means can be provided for stopping the flow of fluid through the siphon tube. The tube may include a primer device intermediate the fluid source and the hollow body inlet which can be used to initiate the flow of fluid. Preferably, a pump injects air into the fluid source, causing the fluid to enter into the tube and travel to the hollow body. A tube extends from the outlet of the hollow body to the fluid source for redirecting the fluid back into the fluid source. The hollow body may include a one-way-valve positioned generally opposite the elastomeric flexible wall which can be used to remove air from the hollow body so that the liquid fills the hollow body and a closed system is created, inject substances into the hollow body for conditioning, or open the system to facilitate draining, if necessary.
In another preferred embodiment of the present invention, the hollow body comprises a portable fluid tank. The flexible and expandable wall includes a rigid portion which extends substantially from the side walls of the hollow body. The rigid portion is capable of reciprocal travel within the hollow body as fluid from the fluid source is added to the hollow body, and as fluid from the hollow body is removed from the outlet thereof.
In yet another embodiment of the present invention, the hollow body comprises a water tower in fluid communication with a fluid source, such as a holding tank or reservoir. A second hollow body has an inlet fluidly connected to the outlet of the hollow body. Means are provided for transporting the fluid from the fluid source, to the hollow body and subsequently to a second hollow body. The means for transferring the fluid from the first hollow body to the second hollow body typically comprises a gravitational flow tube extending from the outlet of the hollow body to the inlet of the second hollow body, the outlet and the hollow body being elevated with respect to the inlet of the second hollow body. The fluid may be returned from the second hollow body to the fluid source. A turbine or the like can also be placed intermediate the hollow body and fluid source, or the hollow body and the second hollow body so that energy can be produced from the fluid flow. In a particular embodiment, the second hollow body has a flexible and expandable wall end thereof, as well as an outlet distal to the flexible and expandable wall. A pump is typically associated with the system for transporting the fluid between the fluid source and the hollow bodies.
In yet another embodiment, the hollow body is fluidly connected to a transportation vehicle, such as an aircraft. The fluid source comprises fuel which is delivered to the hollow body via an elongated tube. A second tube mixed in from an oxygen source to the transportation vehicle to allow the fuel to be combusted at extreme elevations.
In still another embodiment, the system includes a plurality of hollow bodies fluidly connected to one another and positioned in an aircraft such that as fluid is transferred from one hollow body to another, the weight distribution of the airplane is altered resulting in upward, downward, left turn or right turn motions. If necessary, the liquid can be channeled through the rudder or other such flight control mechanism to effectuate these movements.